'10th Timed Challenge' trophy won't register!

Hey everyone, above is the problem I've got at the moment. I'm on my 12th or 13th or something, but it still won't register. I recently lent my account to my friend (so he was logging onto my account on his PS3) - would that have affected anything? I can still earn other trophies, its just this one which I can't.

You lending your account to a friend wouldnt have had an affect on this trophy. Other players have had issues with this one before, and im certain it has been mentioned on this board. If you can, it would be worth looking around for it, or a thread similar, to see if you can find the answers youre looking for. If you dont find anything, just post in here again.